Why does golang need make?

The Go language, commonly known as Golang, is a statically typed, compiled programming language developed and released by Google. With the rapid popularity of Go language in the industry, its performance advantages have increasingly attracted the attention of developers. In the Go language, the make function is a very important function. Its function can be used to create data structures such as slices, maps, or channels of specified types and lengths.

The make function in Go language is not just an ordinary function, but a built-in function (builtin), which has been defined in the source code. The syntax format is:

make(T, size) T

Among them, T represents the data type to be created, size represents the length of the data structure to be created, and the make function returns a pointer to the data structure that has been initialized and the memory has been allocated.

Why use the make function? In fact, the question of why Go language uses the make function is essentially asking why we need dynamic memory allocation. Compared with other programming languages ​​such as C, the memory management of Go language is automated. Even if programmers do not manually manage their memory, the garbage collection mechanism of Go language completes memory recycling. However, in actual development, in order to improve the efficiency of the program, we often need to dynamically allocate and release memory, and using the make function is one of the methods.

In general, the make function of Go language is used to initialize and dynamically allocate memory. In actual development, we mainly use the make function to create data structures such as slices, maps, and channels.

Below, we will explore why we use the make function from three aspects: slicing, mapping, and channels.

1. Slicing

Slicing is an important data structure in the Go language, which is flexible and efficient. Use the make function to quickly create a slice of a specified type and length. When using slices, we can allocate memory space of a specified length through the make function, which can make the operation faster and more concise.

For example:

s := make([]int, 5)
fmt.Println(s)

The above code will create an int slice with a length of 5 and an initial value of 0, and assign it to the variable s. After creating the slice, we can access its elements through s[index].

2. Mapping

Mapping is a data structure of key-value pairs, and it is also one of the commonly used data structures in the Go language. In addition, the mapping is actually a hash table, which is implemented internally through a hash algorithm. Using the make function to create a mapping instance of a specified size can improve the efficiency of the program and make the code clearer and easier to read.

For example:

m := make(map[string]int, 10)
fmt.Println(m)

The above code creates an empty map with an initial capacity of 10 and assigns it to variable m. In Go language, using mapping can achieve fast key-value pair lookup and operation.

3. Channel

Channel is one of the core data structures that runs through concurrent programming in the Go language. It can realize communication between coroutines, making concurrent programming more concise and Intuitive. Channels can be created very easily using the make function. When using a channel, we can allocate a specified size of memory space through the make function, and can achieve synchronization and communication between multiple coroutines.

For example:

c := make(chan int, 5)
fmt.Println(c)

The above code creates a channel with integer content with a buffer size of 5. After creating the channel, we can quickly communicate and synchronize between coroutines through the channel.

Summary

In the Go language, the make function is a very important built-in function, which can be used to create a variety of different data structures. In actual development, we can dynamically allocate memory through the make function to avoid problems such as code memory leaks, and at the same time improve the running efficiency of the program. Therefore, for developers who need to use data structures such as slices, maps, or channels, it is very necessary to be proficient in using the make function.

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